Coffee brewer



July 22, l952 J. R.A CAMPBELL 2,604,031

COFFEE: BREWER BY n July 22, 1952 J. CAMPBELL COFFEE BREWER 5 Sheets-Sheet 2 Filed Dec. 16, 1947 INVENTOR. JAMEJE @4v/56a @www July 22, 1952 J. R. CAMPBELL COFFEE BREWER 5 Sheets-Sheet 5 Filed Dec. 16, 1947 I N V EN TOR.

?- :veA/Y w m c w. W ww Patented July 22, 1952 COFFEE BREWER g y l Y James R; Campbell, Laguna Beach, Calif. Appuootion'neoembor 16, 1947, serial' No. 792,022

yThis invention relates vto coffee brewers and Y 15A claims; (ci. 99-281) pertains more particularly to a coffee brewer of the vacuumv type, having an upper chamber and alower charnber, in which coffee is infused and brewed in the upper chamber and the flow of the brewed coiee from the `upper to the lower chamber isexpedited by creation of a partialfvacuum in the lower chamber.

Coffee brewers of the aforesaid type, which usu-` ally ,conlprise separable upper and lower bowls, are generallyzconsidered to be capable of brew. ing coffee of superior quality, butin their usual form they require vconsiderabler attention and handling during theI brewing process and when the Icoffee has been brewed and is contained in the lowerbowl, the b owls must be separated and the lower bowlr heated individually, ,ornsuitable temperature control means must lbe incorporated in 1,une Source of heat ifit is desiredl to keep the ,v

coffee hot,rin order to avoidurecycling of the brew.V Such conventional coffee brewers furthermorerusually require aseal between the upper and lower bowls, to develop first a pressureand then 4a partial vacuum in thelower bowl, and` these seals, which may be either a gasketed f it,

a glfQllndLor-,lapped fit, or a pressed iit, are the Cause .0i a. .large part of the .breakageenmlnteredwhen` thefbcwls Yare constructed of glass. Not onlymare bowls ,broken by pressure applied manually in fitting them together, 4but theymay the heating and brewing process, Theare'aso'f glassex-posed to heat, or alternativelyl the amount f heat applied to such areas, must be governed by. Vbuilt-in design or be regulated with afview t the pressures, both internal and external,

whichmaybe applied'to such areas. It will be realized that in a sealed structure the degree of v vacuum obtainable does not necessarily have any particular relation to theinitially attained superatmospheric degree of pressure, but may greatly i exceed the latter, and it .frequently does so Ain conventional ccffe'ebrewers when the iilters be tween'the upper and lower bowls become clogged. Proper engineering allowance for such continvA gencies results in restriction of heat-'absorbing areas, .substantial increase `in the thickness of stressed sections, and/or restriction Yofapplicable wattage inelectrically heated brewers, .to any ex# tent ymaterially increasing` the duration of. a brewjn Itis furthermore known that a gentle vacuui produces the best brew' of'coffee, in that it is less likelyto pull 'an excessive amount of sediment1 from the'groundc'offee into the lower chamber if the' filtering means'v is not'v perfectly installeds'v On ,the otherlh'and, aconiplete absence of vac-- be broken by stresses set up in thek glass during v 2 uum extends the time required to brew from the ground coffee.

It is therefore a principal object of this in-"l Ventionto provide a coee brewer which isjautdjv matic in its action of reducing the heat' appli-fy cable in a completed brew of'coffee to a degree.' consistent with keeping the brew warm, thsac-Q, tion being hydraulically actuated by the' breviy itselfin accordance with its' stage of completionf.

Anotherobject of they invention 'is to providea f coffee brewer vwhich has a definite range of superlatmospheric s pressure withinv which its cyclic processie operative,such range 'havinga denit'e' upperflimit which the pressure inthcbr'ewer may not exceed.

A further: object of the'in'vention is to provide y afcoffee brewer which, when adjusted to reduced V"heat furthe purpose of keeping the brew war'm`,1. willV automatically vent any pressure attaining'f operativeI the'range at which its cyclic process is and thereby prevent recycling of the brew.

l Another object of thek invention is to provide a' f. lcoiifee brewer 'which', has a definite' limitirri? the range of the vacuum a'tta'i'nable'.

posed upon during the vcyclic process. A ,n Yet, another .object of theinv'ention vvisto pr vide a coffee lbrewer, in lwhich .definitefliinitsa 'imposed upon'thelpres's'ure, and vacuuin attaingfi able during the cyclic process by'rela't'i'onship to' the columns of water, which may befsupportefd by such pressure andvac'uum, rather' than by 'spring i.

or leve,rz-operated'devices;

A. more derailed'objeotofl the linvention is, to provide a ,coffee brewer' in which the' limitation o'ff pressure and Avacuum i'sQefi'ectedbythe circula;

tion of water between' `two chambers; one of 1, `which is always opento the atmosphere and the other of which` is' vsealed only hydraulically'ffrom the atmosphere', the exhaustion 'of' water from theone to the other breaking a vacuum in the other, j and the exhaustion of water from theother to*A the one breaking a ypressure in said othergchamber Still anotherobject lof the' invention isl rt',0pr0 Vide acoiee brewer having' a vesse1 forvholdin `no gaskets or sealed ground'c'offee and a vessel'for holding water, jd

fining in combination' a pressure c :hamberandI operative on the principle of alternate. pressure and vacuum in theypressure chamber,` `in which joints between the Avessels' A further'object of the invention'i'slt'o provide f a coiiee brewer incorporating its own. electric; 'heating apparatus and having controls reguflat ing the degree of heat which are normally' actuated by the brewl itself passing from one stage o f 1 completion lto another, the removal of the vessel u containing'the brewnecessitating movement of GFF-ICH??? extract theY` 1 tem involving few parts, easily comprehended,

and not easily fouled, worn out or destroyed.

` forithe two vessels is VmountedY for pivotal move( tric heating apparatus of either the open coil type or the brick type.

A further. object lof a coffee brewer in which operative stresses are so minimized that it may suitably be made of;V

glass or other fragile material, which maybe aeoipsi theinvention iste provide l easily taken apart and re-assembled, whichm'a'y-J- be easily and thoroughly cleaned, and which has a simple, effective, and inexpensive control sys- 4 partially shown in broken lines in its position at the start of the brewing cycle;

Fig. 5 is a vertical sectional view from the aspect of Fig. 4 and on the same scale, but taken on the line 5-5 of Fig. 3, and illustrative of the position of the latch mechanism when the lid is in the raisedposition of Figiv1.;

Fig. 6 is `a partly sectional, antlyelevational view similar to Fig. 2, showing the vessels assernbled and lled, with the current to the electric stove turned on at high heat, asV for starting -ab'rew, and the position of the parts indieating near completion of the starting phase of the b'rew cycle;

A Fig. f7. f-is a vertical sectional view similar to Fig. 4, showing the control mechanism in posi- .According to my invention I provide nested 'inner and outer vessels corresponding generally to the usual upper and lower vessels 'and having the usual functions of containing 'respectively the ground lcoffee and the water or finished brew and'adapted to beplaced on a s tov'efo'r, heating, but diife'ring from the; usual construction 'in that th'e' `louter vessel lserves 'as a well whichV the irinfefr'vessel merely restsy or iloats,v vaccording to the 4,water level, andthe inner vessel is fadapted totrap vapor arising 'from the heated vwater in a manner to causejthe water to 'rise inthe well and :to float vthe inner Vessel therein; A-r lid ment, asv by being pivotally Aattached to 1 the "stove, and by its movementV is adapted 'to vcontrohthe heat generated by thestove. The inner'vessel presses the lid upwardly whenloatedjj-and `'is then held 'by the 'lid Aagainst furthe'rupward movement so as to cause the vrising water the well 'to overflow Ainto the inner vessel, vtl'xusnac," compli'shing the infusion 'of "the groundcofife and thereafter permitting the 'lid to. fall when the vdisplacement of waterby the trapped vapor is'co'mpleted. The two movements thus provided fdr-the lid permit the use of an escape'ment inthev heatfcontrol mechanism, which is"fntilia'ed` vnot only tojfc'on'trol.the heat but kalso `,to'latch-:the

T lat-stove I3 and is fitted with ahandie lesecuredy thereto by a bandjfl 51.The stove I3 isprefer--` ably anelectricf heater andfis so-shwn and-'de' lidandfjinner vvesseljin the raised-position until the fhydraulicjconditions 'which 'inducedl that pesitonhave altered.v

vFu;rlthr-r objects "and advantages yof ythe finven tion will either be 4specic'ally pointed 'out in the ensuing description or will'lojeV apparentfromconsideratilorll Vthereof. 'and'"of the 'accompanying drawings fillustrativ'e bf 'preferred embodiments o fftheiinventiongin which: I Figsl is 'a partly exploded elevational view'of a'preferredform of coffee brewer `according tov niy'rventionprovided with an 'electricstova' the inner, for Vinfusion vessel being ,shownraised Vfrom the assemblyas in the :process of insertion or rmoif'al;

F 2 is Ya 'partly sectional, partly elevational viewqfrm the "same aspectasFi'g; `1 but on 'an enl'a'gfdfscale.'showing the 'parts assembled, empty, and 'with the electric stevie turned off, asforstorage Fig. I3 s an elevational view "of the "control -mechanism, taken Vfrom Vthe `viewpoint indicated by 'the arrows 3-3 of Fig. 2 and on aj-further enlarged scale, the Vcover being partly,.brokenv avvayfto expose "the'rnechanism whichjis inthe ldle'or' off, position; i

Fig. 4 isa vertica anisfn shown in Fig. l therepf andon vthe samefscale, and diagrammatically'illustrating" the Vheating coils of thegele'ctric stove, the lpawl of the 'latch mechanism" being lectionalview of the mech- 3tak'en on the line @+4 also 0f" generally cylindrical formandhas an'exlatch mechanism being shown also -in broken-V lines4 as having lcompleted the movement;

Figf is a view similar vto Figs. 2 and-6,fshowing the coiee brewer just passing 4fromthe intermediate phase tothe nal active, or warming' phase ofthe cycle, the transition being vindicated by the positions of the indicator-arrowasfshownf in solidand broken lines; y Y I Fig. -r9f-is a View similarto Figs. 4 an'd '7,-' lillus-v .trating `the position of the vcontrol mechanism atfth'e start and 'completion -of the 'transition mentioned in connection with fFi'gfS; and

Fig'. lOis another view similar to'Figs. 4,*1, and 19,illustrat've of a-'rnodified'form of control mechanism, show-n in the position corresponding 'to` theVv intermediate phase -of vthe brew-`cycle.

Having reference now rtothe details of-'l-the drawings, and particularlyto Figs. l andjZymyinvention comprises an outer vessel I2 vfor hold#v ing-'water to be vheated 4and for receiving 1brewedco'ffee-after the 'heated w-atervhas -infused ground coffee: The vesselIZywhich preferably is of# generally cylindrical form, vnormally 4rests :upon

scribed herein,` but -itis to -be'understood-fthat the principlesl'of' this invention can 'also lbeapplied 'connection with Aother types ofstove-.I' Aie-routwardlyfolfset rim I6 denes the open upper fend; I-'I of the vessel I 2fin a manner providing an f margin of the stove I3, pivotally supports Ianv actuating arm V-2I which 'carriesa lid 22. The lid 22 #is adapted to enter the confines ofthe :flared rim I6 so aste extend over-the 'shoulder' I8 and to cover but ynot to lseal'the -open1end- I'I-of'lthe'vessel I2.

:'An inner vessel 23, having its lupper'portlon formed asan infusion receptacle 24,"is disposed within/'thevessel I2. The vessel 23 is preferably terior "diameter Vslightly less than the 'interior diameter of the vessel, Vso as. to dene therewith an annular space 25 which is'openyto theatmosphere'at its upper end. The oo'r orbcttom o'f'the receptacle V2|I is in the nature of afiglterf wall Z6, from which depends a skirt 21 which normally rests on the bottomwallof `the outer vesselHIZ to support the receptacle within 'said outerjvessel. The skirt V2l and lter-wall 2I'.de lfine"a1-,pressure chamber v28 having an .openinglg at its lower end and the skirt may'be:provided adjacent its llower Aend'with one or more 'operi--- ings, preferably in the'form of aplurality of marginal indentations 23a, which afford communication between thechamberl 28 andthe lower* portion ofthe annular `space 25 when the skirt rests upon the bottom of the vessel I2. vSkirt 21 is formed as an integral lower part of' inner ves-V selV 23, the partition or'filter wall 26 extending transversely, and preferably substantially hori` zontally, across the'interio'r of said inner vessel between the infusion receptacle 24 'and the pressure chamber 28. Y

The receptacle 24 is also provided with an opening 30 adjacent its upper end establishing communication with the upper portion of the an- I nular space .25. The opening 30 is del-med by a rlm'3I at the upper end of vessel 23, and is' disposed at a level below'the shoulder I8 when the skirt 21 is in contact with the bottom lof the vessel I2. A` tubular member 32,- dening a restricted vent passage 33, extends upwardly from the filter-wall 26 tov a level above the upper end ofy the inner vessel23 and preferably above rim I6 of the outer vessel, and has its upper end expandedto form a bulby 34 by which the inner vessel 23 including receptacle 24 may be lifted.

'I'he vessels I2 and 23 may be readily made of glass and are preferably transparent, althoughA it is to be understood that they may be formed of any other suitable material such as enamelware or the like.

The lid-22 has a button 35 on its inner side to which is-secured a sealing pad 36 of resilient material such as soft rubber. The upper surface of the bulb 34 is provided with a raised seat 31 at the end of the :vent passage 33 adapted to be pressed into the' sealing pad 36, by means of which the sealing pad may seal the vent passage 33 when Aheld lat an angle -other than normal thereto. That is to say, the arm 2I may be swung upwardly through a considerable angle, say about tenor fifteen degrees or more before thevsoft resilient sealing pad 36 so disengages from the raised seat 31 as to unseal the vent passage 33, provided that at the same time the tubular member 32 is pressed upwardly so as to maintain the seat andthe -pad in contact.v The annular space 25 permits a slight tilting of the receptacle 24 andtubular member 32 when the inner Vessel rises,'' as v'shown in Fig; 6, and evenv thoughv f arcuate upward movement of the arm 2I relieves pressure on the side of the raised seat 31 on the side'thereof vdistant from the structure 2D more rapidly than on the adjacent side, the raised seat 31 will tend, within the limits of such tilting, to maintain contact with the sealing pad36.

Movementof thejactuating arm 2I and'lid 22 is effected downwardly primarily by gravity and upwardly primarily by pressure ofl the bulb 34 against the sealing-'pad 36, both movements being supplemented under certain conditions fby a hereinafter-described over-center spring.

lid may also be 4raised or lowered manuallyfas v hereinafter described. l I

When water contained inthe vessel I2 is heated to a boil, and the vent passage -33 is sealed by the pad 36,' thevapor from the water'within theA pressure chamber 28 will be vaccumulated therein and by its accumulated pressure will force the water out of the pressure chamber through the open lower end 29 and through the marginal indentations 29a, causing the extruded water to` rise in the annular space 25. The marginal indentations 29a are not essential, as this outward o'w of V`water from theV pressure lchamber can occur between the lower edge of skirt 21 and the bottom wail cf outer vesse1 |2 in the absence of such indentations. The filter-wall 26 is provided r with llter means having small passages affording restricted communication between the interior of receptacle to the vessel I2, but incapable of vent ing a pressure rapidly accumulated in the pressure chamber 28 such as is generated therein when the watertherein is actively boilingVpa'r-L ticularly when partly obstructed by a charge ofground coffee within theinfusion receptacle-24.l The restricted passages of the filter means are also sufciently small in size to substantially pre-:- A. vent passage of moderately ne particles of ground coffee therethrough. Byway of example,

I have found that the provision of four holes 38l of about 0.05 diameter, equally spaced circumferentially in the wall y26, affords adequate re-'f striction of the vapor flow when the heating rate is suflicient to produce moderately rapid boiling and also .substantially prevents passage Vof or.-

dinarygroundv coieeparticles, but affords ade-A quate freedom 'of liquid flow from theA infusion receptacle 24 :upon creation of a partial vacuum in chamber 28.v 1

The infusion receptacle 24 r.and the pressure" chamber 28 have alarge included space compared with the mass of their including walls and filterwall andthe tubular member` 3.2,-and are thereforeV buoyant when surrounded by water, evenk with ,the addition of a charge of dried ground coffee, the relative cubic capacities of the infusion receptacleand the pressure' chamber being such as to enable the former to receive the water contents of the latter as described hereinafter. TheV included space cf the pressure chamber 23y is also very considerably larger in cross-section than the annularspace 25,`so that depression of the water level within the pressure chamber causes a'relatively rapid riseofthe water level in theannular space 25;A and withA a normalinitial charge off water in the vessel I2, therwater rises in-theannularspace'25 to a level at which it iioats the f inner vessel 23: and causes the seat 31fof bulb 34 to press upwardly upon these'alingzpad l35i;

and thereby vcauses upward movement. of the actuating arm 2| while still maintaining a seal atV the upper end of vent passage 33.

Movement of the actuating arm .2I -actuates mechanism included in the structure 20 both to regulate the heat generated bythe stove I3 'and'v to regulate the flotation level of the inner vessel 23; A'Ihe structure 20 comprises a cover 4I hav-- ing' a .slot 42.*(shown in Figs. 3 and 5) in which 1 the arm 2l may be swung, and lparallel'framef plates 43 supporting a shaft 44- to which theA arm 2I'is secured for pivotal movement abouta sub@ stantially horizontal axis. l A second shaft k45 is mounted rotatably inthe frame plates 4,3r belo-w the shaft 44'and is manually controlled by a knob 46 by which it may be rotated, ,contraryV to vthe urging of a coil spring 41, in the direction ofgroe tation in which the varm 2I swings downwardly, that is. as viewed'in Figsi, 5,-7, 9, and 10, ina

clockwise direction, the spring` f41 biasing the' rotaftaneoff. the shaft; in;` the.opnesteedimctimz than the stop pins 5F11: a-nw vbut still.` long enough 'Ime shaiteQ-@earriesa nam-A83. engaeeahleiwi h... an. ieseapement-aformedi by;- themxmalpp tion.; @fame-,armi b :to .resist notatnjefstheisllaf. 15 4,5. .biases im tpepringeh while permitting?.

di t

.Olie Oiliisi. .leef-SD per.-iphelys.4 5.2:.of. the .'eseapement- 4 9.. many.Y also.` ref. str-iet movement.. off. the paewl.- 48:; .1, as it.y willI be. reafli z. ed .f1ao.1fn,Eig;` 5 `H1-.at .when Athe annui isdn, or'approximajseLy-.im theupward positionthereinshown.. clockwise..rotationv of?V theipawl is-.11imited .i 25.` toda positonof contaenwithetheiperiphery.

Moyementf. and posiigion. ofY theY rim? 21. endl. escapemenpidmanesiunther. governed by.. angherisonV spring .iconnectingvanoesetlink 565110. across-4. sidgogtll 1. i ,I.1.e:.Q,1.`9ll '6;1; bankiheldzby. themamepmtes-AZ; y .'l'heoesetvo, In the preferred embodiment 0f `lflnlsg mgentig@ link-v- Sinisi pivot-ally. lnnfnmued.on:theeseepementl the eem; fhsee Switcheemetpeerl.rejection Qf wbyea.pmsmdisposesonthar side ofmtheimeman. minor regiusqeer DiensLeSwitQIf-i. axis-.ofntheeescapement toward whichmheL amm.; I A 2 I f is. inclined; so :bilanune;spring,v 531.A exerts 2.11.2 i over-center downward tension on the". pin'ias 35-A theblaitten may he. moved. fromvoneside-to-the otherf: ofi the.sl'ianii;v` Mi, othis. ovrfc'entertensioni. f urging. the. armld tok either the downward: posil tionshcwszninEigr 2..ontheupwaxrdlposition;shown ,Y n.,Eig-. 5;. the lattenpositiolfl` the armes held 40o;v byy the. end;` margin 42.- of the slo't. 42 aginsi furthenmoyemenhaslurged bythespning. 531` Theoit-set link-SliL avoids intenference! by theshaf-iysofeanoperational', am' and-lby al i-,lfi'ir stop `pin5'9 Y disposed;atfanintermediate position in the pera- 55:... 5 4 tional Law, .aueofrhesepinsf being. serr4 in. mie ffalso. Qf .the the, fname .plalftesf 'Bhestop pin. 53is shoriseuxl from., egigaigegnentf, heatin .'.shoulder F!` into contact with'the fmgerf'i as fshown in Fig. 7, with the circuits to both coils lvcontinuing. tobe closed.y The stop pin k58. pre-4 yvents material further clockwise" rotation of the 'camSI 'by engaging the pawlfY 8. It lwill'be understood that `,the aboveedescribed. sequence -of activation of thevheating coils is reversed when vthe cam'is rotated in theopposita/or counterclockwise; .direction as'urgedfby the spring 4?.

Toenable the operatorto know the position z of the above-'described 4control mechanismwand thefdegree of heat-intensity tobe expected, the

..knob.z46 is provided with an indicator arrow 12.

'start. are indicated onthe cover 4I.

ThreeA positions, marked off .warm, and

The co- .l incidence of the indicator needle 12, respectively,

'with these marks` shows that the pawl 48 is Yagainst thestop pin .51 and the short radiusarc D-F is Adisposed toward the-finger 6B, as shown inFigsI I2 an'dl, and both-heating' coils are disf connected; that thepawl is-against the clockwise aboth coils' 62- andB 3l are connected. r"--Y'Ifo preparea :brew ,ofc'offee *with 'a coffeev brewer embodying 'the preferred fform' of my ini 'ventio'm the" operatorfplaces'fa `charge of coffee C #.(FignGVi'n the infusion. 'receptacle 24, and -a `desiredquantityofwater W in the outer vessel I2,

f and inserts theinner ves's'el23f(with the 4charge offcoiee in' the infusion receptacle) within the cuterwessel.` The 'infusion'receptacle will'require one or. two seconds to settle tothe bottom of the vessel I2, in orderto let air conneclin the pressure chamber 28 escape through the" vent passage A32.v Thel gradual settling* prevents .shock and breakage'when the infusion receptacle and'vessel `arermade, as preferablyfofglassf Whenthe in- Y fusion receptacle has""settled sulhciently" to f per- 'mit thepad 36 to be 'moved'to positionlto seal the vent passage 32,anysmall amount of `air'still requiring venting may gradually escape throughv "the orices 38.`

It will rbe seen,` however, "that Vvvent passage 32 permits'a lmore'rapid escape of hair than the orifices 38,v thereby lesseningfthe "ltlme required to' lower the Sinner' vessel'to the r bottom of the outer vessel. l f

The yoperator may then lower the lid '22 to closed'posltion, and thereafter immediately turn the indicator needle'12 to the lsta-rt position,` pulling Ythe knob 46 outwardly'a little to- Apermit 'Y the pawlV 48ftofpass lthestop pin' 59. The remainder of thefbrewin'g cycle isl then automatic. It'may lbe--noted' here that the operator mayY not move the'indicatorneedleIZ to the start posi-` i tion before closingthelidbecau'se of interference ofl'the fescapement 43""with`the pawld (Fig. 5). This inability 'precludesineiective waste of electricity vwhich wouldAY result from 'accidentally :'.heatingthe .water When'fthe coffee'brewer was "notin position for automatic operation. However, .if the operator wishes to save time'byheat- -i'ngth'eiwater -in the vessel I2 while he is `still engag'ed'in'- charging Ythe infusionv receptacle 'with ground coffee, hefmaylower-thelid'22'upon the 'shoulder' I8, prior'to inserting the vessel 23 in 'the vessel TI2, and then turn; the indicator needle tothe '.startl position. This operation, incivdentally, will boil water for tea or forV other purposes; A- subsequent up and 'down jigglin'g'of' the? 75 lid 22will pass the latch mechanism and control mechanism". through their cycles tothe warm position (shown in brokenlines in Figsr and 9) and. the lid may then be lifted to insert the chargedvinfusionreceptacle, after which the lid can be closed and the indicator needle again turned to the start position.

rfi'At-.the start of the automatic brewing cycle Athe Alid 22L will be in the fully lowered position shown in lig.v 2, and the water will be at the same level in the pressure -chamber 28 andthe annular space 25, asiindicated, for example, bythe'broken line-atL. The movement of. knob ,46 to bringindicator needle 'I2v .to the Astart'positioncauses :cam 6I to close the circuits of both heating coils 62 and 63; lasrtlescribed above, and, since the arm 2I is biased downward by, gravity and also by the over-center spring 53,-notchl 50 engages pawl` 48 (inv the position vshown partially in "broken lines p When the water,A comesto: an' active boil, the =-vapor therefrom will; force the water'ffrom the pressurechamber28 ithrough the marginalfindentations 29d'v into the' annular, spaces 25 and upwardly" therein 'as'shown in Fig. 6,;'causing the inner: vessel Yincluding infusion receptacle 2.4;- to "float .as'heretofore-described; fThelidZZ :and arm -2-I will.belifted'fslightlsT as shown in-ligsi.6 andfF-Z. .1'- When: `the :Water level in the? annular' spacci-25 rises r-sufhciently :above `the water level v 'infthe pressure chamber 28,'i5for examplepas. approximately shown ln'Fi'g. 6, the escapement` ,4.9 will be moved to releasethelpawl 4,8 from thenotch 5I!y asshown in Fig: '1;due to the resulting upward movement of. arm l2l induce'dby the-.oating--of inner vessel-23. if'

lkWhen the pawl is ureleased from thev notch v5l) it willcatch inthe'notch 5I, .finywhi'ch position (as indicated'inbrokenlines. at 48-infFcig7) l-itf will. prevent further `upward rrotation Ofxthe Varm 2I. and. thus preventfurther upward y,flota- --tion ofthe infusion receptacle. However, as'the shoulder yE of' the cam '6I vis now pressing the-iinger '68,."both` ofthe .electric coils-62 and Ii3-are still activated, landthe water will continue to boil and 'therefore lcontinueto rise inthe annular spacers. *..Thearm -2 holds the rimfa'l ofthe innervessel below theilevel of the'rim*V IIcofthe outer vessel which is vimperforate belowfitstopen upper-end, so that the'rising hot water overows theirim A3I into the infusion :receptacle 24 4and infuses thec'offeegrounds therein. r

:The'water overflowing into the Vinfusion receptacle24'will; 'of course, gradually decrease the buoyancy ofr that member but not sufficiently .to cause it to sink vor to release the raised seat 31' Vfrom the-.sealing pad 36. The level ofxwater re- -quired to support' the' inner vessel 23 'infloating position will depend in' part'upon the weight of water-and ground :coffee in the-infusion chamber and'in part upon the Vvolume and pressure of the water 'vapor developed fin 'the pressure; chamber 7 28, 'thesetwo factors of course koperating against eachother." Whilethe water continuesfto flow out'of the pressure chamber-l2 8,' upwardly through `'the' Jannular space 25' and over the. rim 3|, vthe inner vessel willcontinue to float because of the fmaintained upward pressure'of .the vapor in the 'pressure chamber and. the maintained high level of 'thewater' column in. the annular space.

' AIt maybe notedthat'when the inner vessel 23 @is floating, water from'the pressure chamber 28 fin/eed' rio-longer pass through ythe margnalfindentat'ions '2 9ct4 but may` freelyx pass 'through f the 13 a position in which the over-center 'spring pin 56 crosses over the shaft 44, and the spring 53 will then pull the lid and arm 2l upwardly as shown in Figs. l and 5, breaking the seal of the vent passage 33 and releasing the vapor; The pin 5S is so disposed in the escapement 49 that Y this action will occur before the water inthe `annular space 25 reaches the rim of the vessel I2. V1n Fig. l0, I have illustrated a modified form Y of cam intended for use with anelectric stove of the brick type having a terra cotta or similar Vheating surface which holds a'large amount of v l'residual heat when the wattage through the coils l'is reduced. 'Ihe modified cam 'I5 has a` shoulder D' ofminor radius capable of pressing the finger 68 to close the circuit of the low wattage coil B3,

l and a shoulder F' of major radius capable of pressingr'the'nger to close the circuits to both heatingcoils', the intermediate portion of both arcs'D-F being of minor radius incapableof vpressing the nger.

It vv'illbe seen that the modified cam 'F5 corre- --a high wattage coil 62 and a low wattage coil 63 vcontrolled by switch' 64.

"T Thebrewing cycle is correspondingly altered 'when the modified cam`15 is usedfwith a bricktype stove, in that the residual heat of the stove i'srelied onto supply the heat otherwise supplied 'by the heating coils when the pawl 48 is engaged with the escapement notch 5I, and the cam is`in` theintermedi'ate position shown. It will be recalled thatfin this partof the brewing cycle, the water is' being lifted over the rim 31 into the infu- *sion receptacle 24, and that an intensity of heat suicient to cause active boiling is then required.

In this intermediate position of the cam, both VVheating coils ofthe stove are disconnected, but aV brick` type stove of high residual heat will still provide suflicientheat t complete the cycle in the same manner as described above, causing the inner vessel to fall and release' 'pawl 48 fromr "notch l; thus energizing the lowfheat coil in the samemanner asbefore.

' It sometimes happens with v,a brick-type stove thatA the residual heat is sufficient to attempt the recycling of the brew. However, when the infusion receptacle 24 has once settledto the bottom of the vessel I2, the lid 22 is free to rise as noted above, and attempted recycling willthrow it back to the raised position shown in Fig. 5, as

' hereinbefore described, thereby breaking the rei-'' cycling process and warning' the'operat'or that one cycle has beenv completed and thatI` the brewed coffee is readyto serve.

H -aving `described,'certain embodiment/sof myI invention, it will be apparentthat variouschanges therein may occur to persons skilled in the art,

which changes -rnay be made without departing `"fromthe spirit and scope of my invention. Consequently, I wish it understood that the foregoing description is to be construed as Iillu'strative'of,

rather than restrictive upon the appended claims.

I claim: v-1. A coiTee -brewer comprising: a vessel for holding water; means for heating said water adapted for operation at relatively high and relavtivelylo'w heating rates; an 'inner vessel in'sad water-holding vvessel havingA anupper fope'ning ,andfa lower" opening and so" partitioned intermediately ofsaid openings as, when said water isE heatedby operation o-f said heating means at *said relatively high rate, to* confine vapor from y said water and thereby displace said water'upwardly around said inner vessel, and to be lifted buoyantlyf'bysaid displaced-water; latchv means initially movable by the upward-movement of said `4inner "vessel *and then" restrictive fof sata upward movementl so as to permit such upwardly "'fdis'placed' waterv to ilo-w into said upper. opening, thereby depressing said inner vessel vgravitation- A`a`.lly ;s'aid latch means being movable in response to the depression of said inner vessel; and means activated"by the last mentioned movement of said latch means to cause operation-of said heating means Iat'said relatively low rate.

2.`A^coffee brewer comprising: a vessel for holding water; means for heating said 4water yadapted'for operation at relatively high and relajti'vely low heating rates; an infusion receptacle f in said water-holding vessel lhaving an `opening adjacentitsupper end, and having'a skirt ex- "tendigf downwardly below the normal level of "water in saidwateri-holding vessel and forming a pressure vchamber. adapted when said water is heated by operation ofsaid heating means at said relatively high rate to conf-lne vapor from said water Vand thereby displace a portion of said water upwardly, said infusion receptacle being further adapted to then'be liftedbuoyantly V'by said displaced water; latch means initially movableby theupward movement of said infusion ref recptacle and then restrictive of said upward `moverrient so as to permi-t said lupwardly displaced waterV to vflow into said opening, whereby said displac'ed' water ceases to support ysaid'inner vessel and permits said infusion' receptacle to fall gravitationally; said latch being movable in response to such falling movement ofthe infu- "sion receptacle; and control means governing the 'operation' ofy said heating means "and vactivated 4by the last mentioned movement of said latch "means 'to cause operation of said heating means at said relatively low rate.

' thereby to move from said second positioni' 3. 'A coffee lbrewer as set forth in claim 2, said 'control means being manually operable and havving a' first 'position in which said heating means is 'inactivegaisecond position in which said heating means operates at said relatively low rate, and a third position in -which said heating means, operates vatsaid relatively high rate;` and said control means being -engageable by said latch means when in said third position and releasable third-position' to said 4'. A coffee brewer as set forth in" claim 3, including locking means operable when locked to prevent movement of said control means between either of saidl rst and second positions and said 'third position. `5'. vA coiee breweras set forth in'claim 2, in E which said latch 'means includes a member arranged and'constructed so as to be moved upwardly in response to upward movement of said infusion receptacle and to move downwardly Y uponffalling movement of said infusion receptacle; and in which said control means is activated by downward movement of said member.

'6. A coffee brewer as set forth in claim 2, in

- which said pressure chamber is provided with a 'tubular vent' extending upwardly toa position adjacent the upper portion ofv said infusion reeoeptaoleand :said .latchnmeans includes a ,mem-

..fber rnormally in .engagement .with ftheuyppenend sof-said vent to...close the same .and .to .besmoved eresponsivel-y v.to fmovementthereof, ...and .movable ...out-.ofcontaot withsaid vent .toa .lpositionfsuoh Y @as to `.permit isaid .infusion .receptacle .to be ...re- -moved .fromq and :inserted .in: said water-.holding fvessel. f

.e7 AfcoiTee-brewer .asset fo nth.. imolaim Shaving .orice `.mea-ns .communicating between said .insfnsi'on receptacle and'said-pressure.chambenhaving=agpassage-zcapacity normally.permittingyentingzof. pressurerom-saidgpnessure..chamherbut incapablenf-venting,thefpressure.generatedtherevwhen the Ywater. :in said .water-fholding fre--` "ceptacle is .-.actively .:boiling; sai-d -ioriceemeans :.further servilletas a..liquid .freturn '.passagerffrom t' said vzinfusion.iraceptar-:le ...to fsaid .1g-pressure.' chamber when the 'pressuredinrthe :latterqsogpermits 8. A coffee rbrewer ras set forth fin-.claim `6 in ffwhioh .imovement of :said .member .to saidgposi- 2t'ron;permis'sive '.of fremoval :and insertion `.of :fsaid :.:iniusion fre'ceptaole -:prevents .fmovement :of `saidfloontrolI'meanrs :to cause operation :of said :heating meansi at .fsaid relatively :high-frate..

.19. f2-l fcoffeefbrewer-fas-,fset `forthfin claim 2,-.said

. tcontrolz. means :being fnranuallyoperablegand? havingarstposition .in `whichfsaid .heating .means :iszinactive-f la cond; .position:inwhichsaid-f heat- :ing 'means .operates at :said relatively :flow rate,

ancha zthirdgpositionof. zonal fseopeinawhichf said f fheatingz-means foperates fat ssaid relatively vhigh rfrategzfsaid latch means 1 including -a rmember ar- 'franged vand :constructed so las .to :be zmoved ...up-

Y-fwarc'l-ly? by l upward-r movementy .ofzsa-icl. infusion re- '-feeptacleflfand nto move1downwardly-upon f-alling afmovement ofzsaid finfusion receptacle; ...and in `Iwhich said 1'control-means ...is -engageable .bysaid V.zlatch'fmeans-sin lsai-d third ipositionwwhen 'said r2 member :is raised, 'and releasable byfsaid.. latch meanszfor-movement o-saidv secondpositionf upon rdorwnward .movement 'offsaidfmemben :IOL-A1 colee =brewenv aseset forth in1claimf9. in wvliirzlnsaidrcontrol.meansds biased .formovement zfro'm. said Tthi-rd position .f-to said-second rposition,

. ...zand Isaid 'la'toh means includes .fan escapement operable to retain saidwoontrol .means in -said `..thirdfposi-tion whensaid member :is in its lower position .'.and saidzcontrol 'means .is manually placed fin engagementvwith. .said rescapement :and to furtherfretain said;..oontrol :means .-W-thinsthe -`.scopeof:saidethirdgposition whenf-said-.member is rraised, :and to "..release .es-said control means .ffor

' movement to fsaid second :position .upon-down -ffswardmovementfof `said member. Y

:HMA coffeefbrewenfasfset.forth in.v claim 2;.said

' ...contrermeansbeng-manuallyfoperableand:hav-

ing a rst position in which said-lieatingfmeans iis :inactive, =a rfsecond.; position in @which `.heating meanszoperatesfatfsa-id relatively: low; rate, aithird.

eipositionf in whiclfrfsad heatingrmeans operates at 'asaidrelatively :high rate, `:fand fanother position intermediate said second and thirdzpositionin whichfzsaid heating .means .is f-inaetive; saidi con- .trolfmeans ...beingbiasedfore-movementl fromffsaid' ,allygplaced .in .engagement with .said esoapement, tto releasesaid control V`means for Vvmovement to ,said ,intermediate 1position when .said member; is ,raised and .there V'retain :said .control -means and 5 .to release said control means .for movement .to said Tsecond positionupon downward `mov-.ement .of saidmember. f12...A,..coiTee brewer comprising: .a vessel fior .holdingwatem electric means for heating ...said .-water .arranged to-.generate 'alternatively .a A.relaetvelyhigh-.degree and a relatively low .degreeof heat; .an infusion rreceptacle normally supported :by said .vesseltherewthin-:and havingl an opening y:adjacent .its :upper end and .having .suflicient :l5 ...buoyancy .when .containing .a normal chargez-of relatively: dry coiee Yto .be oated upon rrising of ,waterwithin said .vessel .exteriorly of said ...inffusion receptacle; ...a .skirt on said infusion `reneptacle 4.extending fdownwardly therefrom 1below `.tl-ie-ri-iormal level of .water in` said vessel .and ,forming a downwardly opening pressurechamberffor containing .water-'vapor resultant fromft'hefheatfing .ofsaid water Iso -that the pressure. yof .said water .vapor may 'displace the `water .from .said pressure ichamber'iand .force the` water zto .frise V.Within 'sai-d AVessel eXter-iorly of said Askirtwand @said yinfusion receptacle to cause vflotation .there- -nf ;'.saidinfusion receptacle and said :skirt dening .-in combination Awith said Avessel' a ...narrow .annular space communioatingwithsaid opening -'and.aiording:passage forthewater .sol displaced; fla ...tubular vent rextending zupwardly y.from .said pressure chamber to a position:abovefsaid-iaen- 1.infsaidinfusion receptacle; forice .means eommunicating between.- said infusion .receptacle .and .said pressure Achamber `having --a passage capacity :normally permitting venting -of ,pr-Aes- .sure -from :said pressure chamber :but @incapable of venting the.pressure.generatedtherein@when 40 '.thewaterfin said vessel `isactivelylooilingffsaid foriee `.means further serving f as return jpassage :means from; said' infusionfreceptacletosaid-ves- ;..se1f.when the pressure in-said pressure .chamber sopermits ;-.switchvmeans for regulatingsaid-"elecatrio .heating means and havingconsecutive high .heat-'low heat, and 01Tpositions;.controlfmeans vforfzadjusting ..said..switch= means to .any of r said jf positions and` biased `to adjust .said-.switch means fin .consecutive .order .to the oil position; ...latch .means interconnecting.. said 1.infusion receptacle and. saidcontrol means .and having' two; positions, in the rst of whichf-said.latchmeansfsoengages .-.said control .means ..that..said A.switch TIneans is .adjusted to lhigh `heatposition and Y.so-.engages T.A :saidinfusionreceptacle:that theflatter .is yield- .ingly' permitted .limited f flotationand ,said .latch means'` isresponsive to :said notation :tomove. to the scndofsaid .two -positions, .in whichhsaid .latch-means so engages-.said control means 4,and

v .said infusion :receptacle th-at .the .latter...is..con

.-1.3...fAfoolee brewer comprising a-heatilgavessel open at its upper end and imperforate below said open upper end, for containing water to be heated; an infusion receptacle within said vessel and provided at its upper end with an opening adjacent and below the open upper end of the heating vessel; a skirt dependent from the lower end of said infusion receptacle and extending below the normal level of water within said vessel; a transverse lter wall extending across the lower end of said infusion receptacle and cooperating with said skirt to form a downwardly open pressure chamber within said skirt and below said lter wall, said filter wall being provided with restricted filter passage means communicating directly with the interior of said infusion receptacle and with said pressure chamber; a vent tube secured to said transverse lter wall, open at its lower end into said pressure chamber and extending upwardly within said infusion receptacle and open at its upper end above the upper end of the infusion receptacle; and means for sealing said vent tube to permit accumulation of water vapor in said chamber and thereby cause displacement of water from said chamber outwardly beneath said skirt; said lter passage means being insuicient in capacity to vent said pressure chamber of water vapor when the water in said vessel is actively boiling; said vessel defining with said infusion receptacle and said skirt an annular space therebetween to receive water so displaced from said pressure chamber, and said annular space having a iluid capacity substantially less than the uid capacity of said pressure chamber so that when water is iirst admitted to said pressure chamber to a normal operating level and then displaced therefrom into said annular space, the displaced water will ow upwardly through said annular space and into said infusion receptacle.

14. A coffee brewer comprising: an outer vessel adapted to hold water and having a bottom wall and an outer side wall, open at its upper end and imperforate below said open upper end; an inner vessel disposed within said outer vessel and having an inner side wall spaced from said outer side wall to define therebetween an annular passage open to the atmosphere at its upper end, and a transverse lter wall intermediate the height of said inner side wall and cooperating therewith to divide the interior of said inner vessel into an infusion chamber above said filter wall adapted to hold ground coiee and a pressure chamber below said filter wall; said inner vessel having an opening adjacent the lower end thereof permitting flow of Water between said pressure chamber and the lower portion of said annular passage, and having an opening at its upper end adjacent and below the top of said outer side wall to permit water to flow from the upper portion of said annular passage into said infusion chamber; said iilter wall being provided with restricted filter passage means communicating directly with said infusion chamber and with said pressure chamber to permit flow of brewed coffee from said infusion chamber to said pressure chamber, said lter passage means being so restricted in capacity as to obstruct the passage `oi? water vapor formed by heating water contained within said pressure chamber and thereby create pressure of such water vapor beneath said illter wall sufficient to displace water from said pressure chamber upwardly through said annular passage and into said infusion chamber; said inner vessel being provided with a vent passage separate from said restricted passage means, open at its lower end into said pressure chamber and extending upwardly through said infusion chamber and open at its upper end above the infusion chamber, for escape of air from said pressure chamber; and means for sealing said vent passage to prevent escape of water vapor therethrough.

15. A coiee brewer comprising: an outer vessel adapted to hold water and having a bottom wall and an outer side Wall, open at its upper end and imperforate below said open upper end; an inner vesse1 disposed within said outer vessel and having an inner side wall spaced from said outer side wall to dene therebetween an annular passage open to the atmosphere at its upper end, and a transverse filter wall intermediate the height of said inner side wall and cooperating therewith to divide the interior of said inner vessel into an infusion chamber above said iilter wall adapted to hold ground coffee and a pressure chamber below said lter wall; said inner vessel having an opening adjacent the lower end thereof permitting ow of water between said pressure chamber and the lower portion of said annular passage, and having an opening at its upper end adjacent and below the top of said outer side wall to permit water to flow from the upper portion of said annular passage into said infusion chamber; said lter wall being provided with restricted iilter passage means communicating directly with said infusion chamber and with said pressure chamber to permit iiow of brewed coffee from said infusion chamber to said pressure chamber, said lter passage means being so restricted in capacity as to obstruct the passage of water vapor formed by heating Water contained within said pressure chamber and thereby create pressure of such water vapor beneath said lter wall sulcient to displace water from said pressure chamber upwardly through said annular passage and into said infusion chamber; said inner vessel being provided with a vent passage separate from said restricted passage means. open at its lower end into said pressure chamber and extending upwardly through said infusion chamber and open at its upper end above the infusion chamber, for escape of air from said pressure chamber; and a lid formed to extend over` said vessels provided with sealing means and I movable relative to said inner vesse1 to bring said sealing means into and out of engagement with the open upper end of Said vent passage.

JAMES R. CAMPBELL.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 61,122 Tilden Jan. 8, 1867 621,867 Stockett Mar. 28, 1899 1,385,453 Holman July 26, 1921 1,680,571 Routsos Aug. 14, 1928 2,181,246 McNeil Nov. 28, 1939 2,234,741 Schurig Mar. 11, 1941 2,422,580 Meier June 1'7, 194'? FOREIGN PATENTS Number Country Date 18,147 Germany May 16, 1882 138,074 Great Britain May 13, 1920 345,033 Great Britain Mar. 19, 1931 

